In terminology, problem (TR=578), from Greek problema, ‘obstacle’, or pro- ‘forward’ + -ballein ‘to throw’, is a question raised for inquiry, consideration, or solution; a proposition, in mathematics, physics, or philosophy, stating something to be done; an intricate unsettled question; a source of perplexing distress or vexation. [1]

Quotes
The following are related quotes:

“No problem can withstand the assault of sustained thinking.”
Voltaire (c.1760) [3]

“When a problem remains unsolved, general opinion must be wrong.”
Fred Hoyle (c.1965) [2]

“The eternal problem of the human being is how to structure his waking hours. In this existential sense, the function of all social living [existive reacting] is to lend mutual assistance for this project.”
Eric Berne (1964), The Games People Play

“We only think when we are confronted with problems.”
John Dewey (c.1940) [3]

See also
Blue sky problem
Boundary problem
Elective affinities problem
Great problem of natural philosophy
Homework problems
Library walk problem
Modern queries
Reverse engineering puzzle

References
1. Merriam-Webster Collegiate Dictionary, 2000.
2. Harrison, Lionel G. (2011). The Shaping of Life: the Generation of Biological Pattern (pg. 46). Cambridge University Press.
3. Problem quotes – Decision-Making-Solutions.com.

External links
Problem – Wikipedia.
List of unsolved problems – Wikipedia.
List of unsolved problems in philosophy – Wikipedia.
List of unsolved problems in physics – Wikipedia.
List of unsolved problems in mathematics – Wikipedia.

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